Note: Suppose that the gravitational force on object A causes it to accelerate in the direction of object B at 10 m/s(^2). Since object B is half as massive as object A, object B accelerates toward object A at 20 ms(^2), even though the gravitational force on B is of equal magnitude. These values represent the separate accelerations of the objects, but the two bodies are accelerating toward each other at a faster rate. Adding the magnitudes of the objects' individual accelerations gives a value of 30 m/s(^2), the rate at which the objects are accelerating toward each other. Object B is accelerating relative to object A at 30 m/s(^2), but it is accelerating relative to a stationary boundary A at only 20 m/s(^2).